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Naik B, Sasikumar J, Das SP. From Skin and Gut to the Brain: The Infectious Journey of the Human Commensal Fungus Malassezia and Its Neurological Consequences. Mol Neurobiol 2024:10.1007/s12035-024-04270-w. [PMID: 38871941 DOI: 10.1007/s12035-024-04270-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Accepted: 05/27/2024] [Indexed: 06/15/2024]
Abstract
The human mycobiome encompasses diverse communities of fungal organisms residing within the body and has emerged as a critical player in shaping health and disease. While extensive research has focused on the skin and gut mycobiome, recent investigations have pointed toward the potential role of fungal organisms in neurological disorders. Among those fungal organisms, the presence of the commensal fungus Malassezia in the brain has created curiosity because of its commensal nature and primary association with the human skin and gut. This budding yeast is responsible for several diseases, such as Seborrheic dermatitis, Atopic dermatitis, Pityriasis versicolor, Malassezia folliculitis, dandruff, and others. However recent findings surprisingly show the presence of Malassezia DNA in the brain and have been linked to diseases like Alzheimer's disease, Parkinson's disease, Multiple sclerosis, and Amyotrophic lateral sclerosis. The exact role of Malassezia in these disorders is unknown, but its ability to infect human cells, travel through the bloodstream, cross the blood-brain barrier, and reside along with the lipid-rich neuronal cells are potential mechanisms responsible for pathogenesis. This also includes the induction of pro-inflammatory cytokines, disruption of the blood-brain barrier, gut-microbe interaction, and accumulation of metabolic changes in the brain environment. In this review, we discuss these key findings from studies linking Malassezia to neurological disorders, emphasizing the complex and multifaceted nature of these cases. Furthermore, we discuss potential mechanisms through which Malassezia might contribute to the development of neurological conditions. Future investigations will open up new avenues for our understanding of the fungal gut-brain axis and how it influences human behavior. Collaborative research efforts among microbiologists, neuroscientists, immunologists, and clinicians hold promise for unraveling the enigmatic connections between human commensal Malassezia and neurological disorders.
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Affiliation(s)
- Bharati Naik
- Yenepoya Research Centre, Yenepoya (Deemed to be University), Mangalore, 575018, India
| | - Jayaprakash Sasikumar
- Yenepoya Research Centre, Yenepoya (Deemed to be University), Mangalore, 575018, India
| | - Shankar Prasad Das
- Yenepoya Research Centre, Yenepoya (Deemed to be University), Mangalore, 575018, India.
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2
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Pak V, Adewale Q, Bzdok D, Dadar M, Zeighami Y, Iturria-Medina Y. Distinctive whole-brain cell types predict tissue damage patterns in thirteen neurodegenerative conditions. eLife 2024; 12:RP89368. [PMID: 38512130 PMCID: PMC10957173 DOI: 10.7554/elife.89368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/22/2024] Open
Abstract
For over a century, brain research narrative has mainly centered on neuron cells. Accordingly, most neurodegenerative studies focus on neuronal dysfunction and their selective vulnerability, while we lack comprehensive analyses of other major cell types' contribution. By unifying spatial gene expression, structural MRI, and cell deconvolution, here we describe how the human brain distribution of canonical cell types extensively predicts tissue damage in 13 neurodegenerative conditions, including early- and late-onset Alzheimer's disease, Parkinson's disease, dementia with Lewy bodies, amyotrophic lateral sclerosis, mutations in presenilin-1, and 3 clinical variants of frontotemporal lobar degeneration (behavioral variant, semantic and non-fluent primary progressive aphasia) along with associated three-repeat and four-repeat tauopathies and TDP43 proteinopathies types A and C. We reconstructed comprehensive whole-brain reference maps of cellular abundance for six major cell types and identified characteristic axes of spatial overlapping with atrophy. Our results support the strong mediating role of non-neuronal cells, primarily microglia and astrocytes, in spatial vulnerability to tissue loss in neurodegeneration, with distinct and shared across-disorder pathomechanisms. These observations provide critical insights into the multicellular pathophysiology underlying spatiotemporal advance in neurodegeneration. Notably, they also emphasize the need to exceed the current neuro-centric view of brain diseases, supporting the imperative for cell-specific therapeutic targets in neurodegeneration.
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Affiliation(s)
- Veronika Pak
- Department of Neurology and Neurosurgery, McGill UniversityMontrealCanada
- McConnell Brain Imaging Centre, Montreal Neurological InstituteMontrealCanada
- Ludmer Centre for Neuroinformatics & Mental HealthMontrealCanada
| | - Quadri Adewale
- Department of Neurology and Neurosurgery, McGill UniversityMontrealCanada
- McConnell Brain Imaging Centre, Montreal Neurological InstituteMontrealCanada
- Ludmer Centre for Neuroinformatics & Mental HealthMontrealCanada
| | - Danilo Bzdok
- McConnell Brain Imaging Centre, Montreal Neurological InstituteMontrealCanada
- Department of Biomedical Engineering, McGill UniversityMontrealCanada
- School of Computer Science, McGill UniversityMontrealCanada
- Mila – Quebec Artificial Intelligence InstituteMontrealCanada
| | | | | | - Yasser Iturria-Medina
- Department of Neurology and Neurosurgery, McGill UniversityMontrealCanada
- McConnell Brain Imaging Centre, Montreal Neurological InstituteMontrealCanada
- Ludmer Centre for Neuroinformatics & Mental HealthMontrealCanada
- Department of Biomedical Engineering, McGill UniversityMontrealCanada
- McGill Centre for Studies in AgingMontrealCanada
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3
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Wang H, Liu YT, Ren YL, Guo XY, Wang Y. Association of peripheral immune activation with amyotrophic lateral sclerosis and Parkinson's disease: A systematic review and meta-analysis. J Neuroimmunol 2024; 388:578290. [PMID: 38301596 DOI: 10.1016/j.jneuroim.2024.578290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 11/19/2023] [Accepted: 01/11/2024] [Indexed: 02/03/2024]
Abstract
BACKGROUND Recent studies have revealed the link between immune activation and neurodegenerative diseases. METHODS By employing meta-analysis, we estimated the standardized mean difference (SMD) and their corresponding 95% confidence intervals (CIs) between the groups. RESULTS According to the pre-set criteria, a total of 21 published articles including 2377 ALS patients and 1244 HCs, as well as 60 articles including 5111 PD patients and 4237 HCs, were identified. This study provided evidence of peripheral immune activation in the pathogenesis of ALS and PD. CONCLUSION Our results suggested monitoring changes in peripheral blood immune cell populations, particularly lymphocyte subsets, will benefit understanding the developments and exploring reliable and specific biomarkers of these two diseases.
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Affiliation(s)
- Han Wang
- Department of Pathophysiology, West China College of Basic Medical Sciences & Forensic Medicine, Sichuan University, Chengdu 610041, China
| | - Yi-Ti Liu
- Department of Neurology, Neurological Diseases and Brain Function Laboratory, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Yan-Ling Ren
- Department of Pathophysiology, West China College of Basic Medical Sciences & Forensic Medicine, Sichuan University, Chengdu 610041, China
| | - Xiao-Yan Guo
- Department of Neurology, Neurological Diseases and Brain Function Laboratory, The Affiliated Hospital of Southwest Medical University, Luzhou, China.
| | - Yi Wang
- Department of Pathophysiology, West China College of Basic Medical Sciences & Forensic Medicine, Sichuan University, Chengdu 610041, China.
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D’Angiolini S, Lui M, Mazzon E, Calabrò M. Network Analysis Performed on Transcriptomes of Parkinson's Disease Patients Reveals Dysfunction in Protein Translation. Int J Mol Sci 2024; 25:1299. [PMID: 38279299 PMCID: PMC10816150 DOI: 10.3390/ijms25021299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2023] [Revised: 01/17/2024] [Accepted: 01/19/2024] [Indexed: 01/28/2024] Open
Abstract
Parkinson's disease (PD) is a prevalent neurodegenerative disorder characterized by the progressive degeneration of dopaminergic neurons in the substantia nigra region of the brain. The hallmark pathological feature of PD is the accumulation of misfolded proteins, leading to the formation of intracellular aggregates known as Lewy bodies. Recent data evidenced how disruptions in protein synthesis, folding, and degradation are events commonly observed in PD and may provide information on the molecular background behind its etiopathogenesis. In the present study, we used a publicly available transcriptomic microarray dataset of peripheral blood of PD patients and healthy controls (GSE6613) to investigate the potential dysregulation of elements involved in proteostasis-related processes at the transcriptomic level. Our bioinformatics analysis revealed 375 differentially expressed genes (DEGs), of which 281 were down-regulated and 94 were up-regulated. Network analysis performed on the observed DEGs highlighted a cluster of 36 elements mainly involved in the protein synthesis processes. Different enriched ontologies were related to translation initiation and regulation, ribosome structure, and ribosome components nuclear export. Overall, this data consistently points to a generalized impairment of the translational machinery and proteostasis. Dysregulation of these mechanics has been associated with PD pathogenesis. Understanding the precise regulation of such processes may shed light on the molecular mechanisms of PD and provide potential data for early diagnosis.
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Affiliation(s)
| | | | - Emanuela Mazzon
- IRCCS Centro Neurolesi “Bonino-Pulejo”, Via Provinciale Palermo, Contrada Casazza, 98124 Messina, Italy
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Manole A, Wong T, Rhee A, Novak S, Chin SM, Tsimring K, Paucar A, Williams A, Newmeyer TF, Schafer ST, Rosh I, Kaushik S, Hoffman R, Chen S, Wang G, Snyder M, Cuervo AM, Andrade L, Manor U, Lee K, Jones JR, Stern S, Marchetto MC, Gage FH. NGLY1 mutations cause protein aggregation in human neurons. Cell Rep 2023; 42:113466. [PMID: 38039131 PMCID: PMC10826878 DOI: 10.1016/j.celrep.2023.113466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 08/04/2023] [Accepted: 11/03/2023] [Indexed: 12/03/2023] Open
Abstract
Biallelic mutations in the gene that encodes the enzyme N-glycanase 1 (NGLY1) cause a rare disease with multi-symptomatic features including developmental delay, intellectual disability, neuropathy, and seizures. NGLY1's activity in human neural cells is currently not well understood. To understand how NGLY1 gene loss leads to the specific phenotypes of NGLY1 deficiency, we employed direct conversion of NGLY1 patient-derived induced pluripotent stem cells (iPSCs) to functional cortical neurons. Transcriptomic, proteomic, and functional studies of iPSC-derived neurons lacking NGLY1 function revealed several major cellular processes that were altered, including protein aggregate-clearing functionality, mitochondrial homeostasis, and synaptic dysfunctions. These phenotypes were rescued by introduction of a functional NGLY1 gene and were observed in iPSC-derived mature neurons but not astrocytes. Finally, laser capture microscopy followed by mass spectrometry provided detailed characterization of the composition of protein aggregates specific to NGLY1-deficient neurons. Future studies will harness this knowledge for therapeutic development.
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Affiliation(s)
- Andreea Manole
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Thomas Wong
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Amanda Rhee
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Sammy Novak
- Waitt Advanced Biophotonics Core, Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Shao-Ming Chin
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Katya Tsimring
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Andres Paucar
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - April Williams
- The Razavi Newman Integrative Genomics and Bioinformatics Core Facility, Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Traci Fang Newmeyer
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Simon T Schafer
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Idan Rosh
- Sagol Department of Neurobiology, Faculty of Natural Sciences, University of Haifa, Haifa, Israel
| | - Susmita Kaushik
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA; Institute for Aging Studies, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Rene Hoffman
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Songjie Chen
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Guangwen Wang
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Michael Snyder
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Ana Maria Cuervo
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA; Institute for Aging Studies, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Leo Andrade
- Waitt Advanced Biophotonics Core, Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Uri Manor
- Waitt Advanced Biophotonics Core, Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Kevin Lee
- Grace Science Foundation, Menlo Park, CA 94025, USA
| | - Jeffrey R Jones
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Shani Stern
- Sagol Department of Neurobiology, Faculty of Natural Sciences, University of Haifa, Haifa, Israel
| | - Maria C Marchetto
- Department of Anthropology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Fred H Gage
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA.
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Lambert-Smith IA, Saunders DN, Yerbury JJ. Progress in biophysics and molecular biology proteostasis impairment and ALS. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2022; 174:3-27. [PMID: 35716729 DOI: 10.1016/j.pbiomolbio.2022.06.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 05/19/2022] [Accepted: 06/09/2022] [Indexed: 12/11/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a rapidly progressive and fatal neurodegenerative disease that results from the loss of both upper and lower motor neurons. It is the most common motor neuron disease and currently has no effective treatment. There is mounting evidence to suggest that disturbances in proteostasis play a significant role in ALS pathogenesis. Proteostasis is the maintenance of the proteome at the right level, conformation and location to allow a cell to perform its intended function. In this review, we present a thorough synthesis of the literature that provides evidence that genetic mutations associated with ALS cause imbalance to a proteome that is vulnerable to such pressure due to its metastable nature. We propose that the mechanism underlying motor neuron death caused by defects in mRNA metabolism and protein degradation pathways converges on proteostasis dysfunction. We propose that the proteostasis network may provide an effective target for therapeutic development in ALS.
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Affiliation(s)
- Isabella A Lambert-Smith
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia; Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Darren N Saunders
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia
| | - Justin J Yerbury
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia; Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia.
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7
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Logan R, Dubel-Haag J, Schcolnicov N, Miller SJ. Novel Genetic Signatures Associated With Sporadic Amyotrophic Lateral Sclerosis. Front Genet 2022; 13:851496. [PMID: 35401706 PMCID: PMC8986983 DOI: 10.3389/fgene.2022.851496] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 02/14/2022] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic Lateral Sclerosis (ALS) is a complex polygenetic neurodegenerative disorder. Establishing a diagnosis for ALS is a challenging and lengthy process. By the time a diagnosis is made, the lifespan prognosis is only about two to 5 years. Genetic testing can be critical in assessing a patient’s risk for ALS, provided they have one of the known familial genes. However, the vast majority of ALS cases are sporadic and have no known associated genetic signatures. Our analysis of the whole genome sequencing data from ALS patients and healthy controls from the Answer ALS Consortium has uncovered twenty-three novel mutations in twenty-two protein-coding genes associated with sporadic ALS cases. The results show the majority of patients with the sporadic form of ALS have at least one or more mutation(s) in the 22 genes we have identified with probabilities of developing ALS ranging from 25–99%, depending on the number of mutations a patient has among the identified genes. Moreover, we have identified a subset of the ALS cohort that has >17 mutations in the 22 identified. In this case, a patient with this mutation profile has a 99% chance of developing ALS and could be classified as being at high risk for the disease. These genetic biomarkers can be used as an early ALS disease diagnostic tool with a rapid and non-invasive technique.
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Affiliation(s)
- Robert Logan
- Pluripotent Diagnostics Corp, Colorado Springs, CO, United States
- Department of Biology, Eastern Nazarene College, Quincy, MA, United States
| | | | | | - Sean J. Miller
- Pluripotent Diagnostics Corp, Colorado Springs, CO, United States
- *Correspondence: Sean J. Miller,
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8
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Goyal S, Seth B, Chaturvedi RK. Polyphenols and Stem Cells for Neuroregeneration in Parkinson's Disease and Amyotrophic Lateral Sclerosis. Curr Pharm Des 2021; 28:806-828. [PMID: 34781865 DOI: 10.2174/1381612827666211115154450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Accepted: 11/02/2021] [Indexed: 11/22/2022]
Abstract
Parkinson's disease (PD) and Amyotrophic lateral sclerosis (ALS) are neurological disorders, pathologically characterized by chronic degeneration of dopaminergic neurons and motor neurons respectively. There is still no cure or effective treatment against the disease progression and most of the treatments are symptomatic. The present review offers an overview of the different factors involved in the pathogenesis of these diseases. Subsequently, we focused on the recent advanced studies of dietary polyphenols and stem cell therapies, which have made it possible to slow down the progression of neurodegeneration. To date, stem cells and different polyphenols have been used for the directional induction of neural stem cells into dopaminergic neurons and motor neurons. We have also discussed their involvement in the modulation of different signal transduction pathways and growth factor levels in various in vivo and in vitro studies. Likewise stem cells, polyphenols also exhibit the potential of neuroprotection by their anti-apoptotic, anti-inflammatory, anti-oxidant properties regulating the growth factors levels and molecular signaling events. Overall this review provides a detailed insight into recent strategies that promise the use of polyphenol with stem cell therapy for the possible treatment of PD and ALS.
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Affiliation(s)
- Shweta Goyal
- Developmental Toxicology Laboratory, Systems Toxicology and Health Risk Assessment Group, CSIR-Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, Uttar Pradesh 226001. India
| | - Brashket Seth
- Developmental Toxicology Laboratory, Systems Toxicology and Health Risk Assessment Group, CSIR-Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, Uttar Pradesh 226001. India
| | - Rajnish Kumar Chaturvedi
- Developmental Toxicology Laboratory, Systems Toxicology and Health Risk Assessment Group, CSIR-Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, Uttar Pradesh 226001. India
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Protein Synthesis in the Developing Neocortex at Near-Atomic Resolution Reveals Ebp1-Mediated Neuronal Proteostasis at the 60S Tunnel Exit. Mol Cell 2020; 81:304-322.e16. [PMID: 33357414 DOI: 10.1016/j.molcel.2020.11.037] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 09/04/2020] [Accepted: 11/19/2020] [Indexed: 02/07/2023]
Abstract
Protein synthesis must be finely tuned in the developing nervous system as the final essential step of gene expression. This study investigates the architecture of ribosomes from the neocortex during neurogenesis, revealing Ebp1 as a high-occupancy 60S peptide tunnel exit (TE) factor during protein synthesis at near-atomic resolution by cryoelectron microscopy (cryo-EM). Ribosome profiling demonstrated Ebp1-60S binding is highest during start codon initiation and N-terminal peptide elongation, regulating ribosome occupancy of these codons. Membrane-targeting domains emerging from the 60S tunnel, which recruit SRP/Sec61 to the shared binding site, displace Ebp1. Ebp1 is particularly abundant in the early-born neural stem cell (NSC) lineage and regulates neuronal morphology. Ebp1 especially impacts the synthesis of membrane-targeted cell adhesion molecules (CAMs), measured by pulsed stable isotope labeling by amino acids in cell culture (pSILAC)/bioorthogonal noncanonical amino acid tagging (BONCAT) mass spectrometry (MS). Therefore, Ebp1 is a central component of protein synthesis, and the ribosome TE is a focal point of gene expression control in the molecular specification of neuronal morphology during development.
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Yan P, Ren J, Zhang W, Qu J, Liu GH. Protein quality control of cell stemness. CELL REGENERATION (LONDON, ENGLAND) 2020; 9:22. [PMID: 33179756 PMCID: PMC7658286 DOI: 10.1186/s13619-020-00064-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 09/14/2020] [Indexed: 02/07/2023]
Abstract
Protein quality control (PQC) systems play essential roles in the recognition, refolding and clearance of aberrant proteins, thus ensuring cellular protein homeostasis, or proteostasis. Especially, continued proliferation and differentiation of stem cells require a high rate of translation; therefore, accurate PQC systems are essential to maintain stem cell function. Growing evidence suggested crucial roles of PQC systems in regulating the stemness and differentiation of stem cells. This review focuses on current knowledge regarding the components of the proteostasis network in stem cells, and the importance of proteostasis in maintaining stem cell identity and regenerative functions. A complete understanding of this process might uncover potential applications in aging intervention and aging-related diseases.
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Affiliation(s)
- Pengze Yan
- State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jie Ren
- University of Chinese Academy of Sciences, Beijing, 100049, China
- China National Center for Bioinformation, Beijing, 100101, China
- CAS Key Laboratory of Genomic and Precision Medicine, Collaborative Innovation Center of Genetics and Development, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, 100101, China
- Institute for Stem cell and Regeneration, Chinese Academy of Sciences, Beijing, 100101, China
| | - Weiqi Zhang
- University of Chinese Academy of Sciences, Beijing, 100049, China.
- China National Center for Bioinformation, Beijing, 100101, China.
- CAS Key Laboratory of Genomic and Precision Medicine, Collaborative Innovation Center of Genetics and Development, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, 100101, China.
- Institute for Stem cell and Regeneration, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Jing Qu
- University of Chinese Academy of Sciences, Beijing, 100049, China.
- Institute for Stem cell and Regeneration, Chinese Academy of Sciences, Beijing, 100101, China.
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Guang-Hui Liu
- State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
- Institute for Stem cell and Regeneration, Chinese Academy of Sciences, Beijing, 100101, China.
- Beijing Institute for Brain Disorders, Advanced Innovation Center for Human Brain Protection, National Clinical Research Center for Geriatric Disorders, Xuanwu Hospital Capital Medical University, Beijing, 100053, China.
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11
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Isaacs BR, Keuken MC, Alkemade A, Temel Y, Bazin PL, Forstmann BU. Methodological Considerations for Neuroimaging in Deep Brain Stimulation of the Subthalamic Nucleus in Parkinson's Disease Patients. J Clin Med 2020; 9:E3124. [PMID: 32992558 PMCID: PMC7600568 DOI: 10.3390/jcm9103124] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 09/17/2020] [Accepted: 09/25/2020] [Indexed: 12/17/2022] Open
Abstract
Deep brain stimulation (DBS) of the subthalamic nucleus is a neurosurgical intervention for Parkinson's disease patients who no longer appropriately respond to drug treatments. A small fraction of patients will fail to respond to DBS, develop psychiatric and cognitive side-effects, or incur surgery-related complications such as infections and hemorrhagic events. In these cases, DBS may require recalibration, reimplantation, or removal. These negative responses to treatment can partly be attributed to suboptimal pre-operative planning procedures via direct targeting through low-field and low-resolution magnetic resonance imaging (MRI). One solution for increasing the success and efficacy of DBS is to optimize preoperative planning procedures via sophisticated neuroimaging techniques such as high-resolution MRI and higher field strengths to improve visualization of DBS targets and vasculature. We discuss targeting approaches, MRI acquisition, parameters, and post-acquisition analyses. Additionally, we highlight a number of approaches including the use of ultra-high field (UHF) MRI to overcome limitations of standard settings. There is a trade-off between spatial resolution, motion artifacts, and acquisition time, which could potentially be dissolved through the use of UHF-MRI. Image registration, correction, and post-processing techniques may require combined expertise of traditional radiologists, clinicians, and fundamental researchers. The optimization of pre-operative planning with MRI can therefore be best achieved through direct collaboration between researchers and clinicians.
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Affiliation(s)
- Bethany R. Isaacs
- Integrative Model-based Cognitive Neuroscience Research Unit, University of Amsterdam, 1018 WS Amsterdam, The Netherlands; (A.A.); (P.-L.B.); (B.U.F.)
- Department of Experimental Neurosurgery, Maastricht University Medical Center, 6202 AZ Maastricht, The Netherlands;
| | - Max C. Keuken
- Municipality of Amsterdam, Services & Data, Cluster Social, 1000 AE Amsterdam, The Netherlands;
| | - Anneke Alkemade
- Integrative Model-based Cognitive Neuroscience Research Unit, University of Amsterdam, 1018 WS Amsterdam, The Netherlands; (A.A.); (P.-L.B.); (B.U.F.)
| | - Yasin Temel
- Department of Experimental Neurosurgery, Maastricht University Medical Center, 6202 AZ Maastricht, The Netherlands;
| | - Pierre-Louis Bazin
- Integrative Model-based Cognitive Neuroscience Research Unit, University of Amsterdam, 1018 WS Amsterdam, The Netherlands; (A.A.); (P.-L.B.); (B.U.F.)
- Max Planck Institute for Human Cognitive and Brain Sciences, D-04103 Leipzig, Germany
| | - Birte U. Forstmann
- Integrative Model-based Cognitive Neuroscience Research Unit, University of Amsterdam, 1018 WS Amsterdam, The Netherlands; (A.A.); (P.-L.B.); (B.U.F.)
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12
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Tang BL. RAB39B's role in membrane traffic, autophagy, and associated neuropathology. J Cell Physiol 2020; 236:1579-1592. [PMID: 32761840 DOI: 10.1002/jcp.29962] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 06/19/2020] [Accepted: 07/13/2020] [Indexed: 12/14/2022]
Abstract
Neuropathological disorders are increasingly associated with dysfunctions in neuronal membrane traffic and autophagy, with defects among members of the Rab family of small GTPases implicated. Mutations in the human Xq28 localized gene RAB39B have been associated with X-linked neurodevelopmental defects including macrocephaly, intellectual disability, autism spectrum disorder (ASD), as well as rare cases of early-onset Parkinson's disease (PD). Despite the finding that RAB39B regulates GluA2 trafficking and could thus influence synaptic α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor subunit composition, reasons for the wide-ranging neuropathological consequences associated with RAB39B defects have been unclear. Recent studies have now unraveled possible mechanisms underlying the neuropathological roles of this brain-enriched small GTPase. Studies in RAB39B knockout mice showed that RAB39B interacts with components of Class I phosphatidylinositol-3-kinase (PI3K) signaling. In its absence, the PI3K-AKT-mechanistic target of rapamycin signaling pathway in neural progenitor cells (NPCs) is hyperactivated, which promotes NPC proliferation, leading to macrocephaly and ASD. Pertaining to early-onset PD, a complex of C9orf72, Smith-Magenis syndrome chromosome region candidate 8 and WD repeat domain 41 that functions in autophagy has been identified as a guanine nucleotide exchange factor of RAB39B. Here, recent findings that have shed light on our mechanistic understanding of RAB39B's role in neurodevelopmental and neurodegenerative pathologies are reviewed. Caveats and unanswered questions are also discussed, and future perspectives outlined.
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Affiliation(s)
- Bor Luen Tang
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,NUS Graduate School of Integrative Sciences and Engineering, National University of Singapore, Singapore
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13
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Zhang C, Ötjengerdes RM, Roewe J, Mejias R, Marschall ALJ. Applying Antibodies Inside Cells: Principles and Recent Advances in Neurobiology, Virology and Oncology. BioDrugs 2020; 34:435-462. [PMID: 32301049 PMCID: PMC7391400 DOI: 10.1007/s40259-020-00419-w] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
To interfere with cell function, many scientists rely on methods that target DNA or RNA due to the ease with which they can be applied. Proteins are usually the final executors of function but are targeted only indirectly by these methods. Recent advances in targeted degradation of proteins based on proteolysis-targeting chimaeras (PROTACs), ubiquibodies, deGradFP (degrade Green Fluorescent Protein) and other approaches have demonstrated the potential of interfering directly at the protein level for research and therapy. Proteins can be targeted directly and very specifically by antibodies, but using antibodies inside cells has so far been considered to be challenging. However, it is possible to deliver antibodies or other proteins into the cytosol using standard laboratory equipment. Physical methods such as electroporation have been demonstrated to be efficient and validated thoroughly over time. The expression of intracellular antibodies (intrabodies) inside cells is another way to interfere with intracellular targets at the protein level. Methodological strategies to target the inside of cells with antibodies, including delivered antibodies and expressed antibodies, as well as applications in the research areas of neurobiology, viral infections and oncology, are reviewed here. Antibodies have already been used to interfere with a wide range of intracellular targets. Disease-related targets included proteins associated with neurodegenerative diseases such as Parkinson's disease (α-synuclein), Alzheimer's disease (amyloid-β) or Huntington's disease (mutant huntingtin [mHtt]). The applications of intrabodies in the context of viral infections include targeting proteins associated with HIV (e.g. HIV1-TAT, Rev, Vif, gp41, gp120, gp160) and different oncoviruses such as human papillomavirus (HPV), hepatitis B virus (HBV), hepatitis C virus (HCV) and Epstein-Barr virus, and they have been used to interfere with various targets related to different processes in cancer, including oncogenic pathways, proliferation, cell cycle, apoptosis, metastasis, angiogenesis or neo-antigens (e.g. p53, human epidermal growth factor receptor-2 [HER2], signal transducer and activator of transcription 3 [STAT3], RAS-related RHO-GTPase B (RHOB), cortactin, vascular endothelial growth factor receptor 2 [VEGFR2], Ras, Bcr-Abl). Interfering at the protein level allows questions to be addressed that may remain unanswered using alternative methods. This review addresses why direct targeting of proteins allows unique insights, what is currently feasible in vitro, and how this relates to potential therapeutic applications.
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Affiliation(s)
- Congcong Zhang
- Georg-Speyer-Haus, Institute for Tumor Biology and Experimental Therapy, Frankfurt am Main, Germany
- German Cancer Consortium (DKTK), Partner Site Frankfurt/Mainz, Frankfurt am Main, Germany
- German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Rina M Ötjengerdes
- Hannover Medical School (MHH), Carl-Neuberg-Straße 1, 30625, Hannover, Germany
| | - Julian Roewe
- German Cancer Consortium (DKTK) Clinical Cooperation Unit (CCU) Neuroimmunology and Brain TumorImmunology (D170), German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Rebeca Mejias
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Andrea L J Marschall
- Technische Universität Braunschweig, Institute of Biochemistry, Biotechnology and Bioinformatics, Brunswick, Germany.
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14
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Myszczynska MA, Ojamies PN, Lacoste AMB, Neil D, Saffari A, Mead R, Hautbergue GM, Holbrook JD, Ferraiuolo L. Applications of machine learning to diagnosis and treatment of neurodegenerative diseases. Nat Rev Neurol 2020; 16:440-456. [DOI: 10.1038/s41582-020-0377-8] [Citation(s) in RCA: 105] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/09/2020] [Indexed: 12/11/2022]
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15
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Harlen KM, Roush EC, Clayton JE, Martinka S, Hughes TE. Live-Cell Assays for Cell Stress Responses Reveal New Patterns of Cell Signaling Caused by Mutations in Rhodopsin, α-Synuclein and TDP-43. Front Cell Neurosci 2019; 13:535. [PMID: 31920544 PMCID: PMC6930162 DOI: 10.3389/fncel.2019.00535] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 11/19/2019] [Indexed: 12/15/2022] Open
Abstract
Many neurodegenerative diseases induce high levels of sustained cellular stress and alter a number of cellular processes. To examine how different mutations associated with neurodegenerative disease affect cell stress and signaling, we created live-cell assays for endoplasmic reticulum (ER)-mediated cell stress and second messenger signaling. We first examined neurodegenerative mutations associated with direct ER stress by exploring the effect of rhodopsin mutations on ER stress and Ca2+ signaling. The rhodopsin P23H mutation, the most common mutation in autosomal dominant Retinitis Pigmentosa (RP), produced increased ER stress levels compared to wild type (WT) rhodopsin. Moreover, this increase in cell stress correlated with blunted Ca2+ signaling in a stress-dependent manner. Analysis of single-cell Ca2+ signaling profiles revealed unique Ca2+ signaling responses exist in cells expressing WT or P23H rhodopsin, consistent with the idea that second messenger signaling is affected by cell stress. To explore the use of the ER-stress biosensor in neurodegenerative diseases that may not have a direct effect on ER-mediated cell stress, we examined how various mutants of α-synuclein and TDP-43 affected ER stress. Mutants of both α-synuclein and TDP-43 associated with Parkinson's disease (PD) and Amyotrophic lateral sclerosis (ALS) demonstrated increased ER stress compared to WT proteins. To examine the effect of α-synuclein and TDP-43 mutants on cellular signaling, we created a second live-cell assay to monitor changes in cAMP signaling during expression of various forms of α-synuclein and TDP-43. The increased cell stress caused by expression of the mutant proteins was accompanied by changes in phosphodiesterase activity. Both HEK293T and SH-SY5Y cells expressing these proteins displayed a shift towards increased cAMP degradation rates, likely due to increased phosphodiesterase activity. Together these data illustrate how biosensors for cellular stress and signaling can provide nuanced, new views of neurodegenerative disease processes.
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16
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Nehammer C, Ejlerskov P, Gopal S, Handley A, Ng L, Moreira P, Lee H, Issazadeh-Navikas S, Rubinsztein DC, Pocock R. Interferon-β-induced miR-1 alleviates toxic protein accumulation by controlling autophagy. eLife 2019; 8:49930. [PMID: 31799933 PMCID: PMC6914338 DOI: 10.7554/elife.49930] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Accepted: 12/03/2019] [Indexed: 12/22/2022] Open
Abstract
Appropriate regulation of autophagy is crucial for clearing toxic proteins from cells. Defective autophagy results in accumulation of toxic protein aggregates that detrimentally affect cellular function and organismal survival. Here, we report that the microRNA miR-1 regulates the autophagy pathway through conserved targeting of the orthologous Tre-2/Bub2/CDC16 (TBC) Rab GTPase-activating proteins TBC-7 and TBC1D15 in Caenorhabditis elegans and mammalian cells, respectively. Loss of miR-1 causes TBC-7/TBC1D15 overexpression, leading to a block on autophagy. Further, we found that the cytokine interferon-β (IFN-β) can induce miR-1 expression in mammalian cells, reducing TBC1D15 levels, and safeguarding against proteotoxic challenges. Therefore, this work provides a potential therapeutic strategy for protein aggregation disorders.
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Affiliation(s)
- Camilla Nehammer
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia.,Biotech Research and Innovation Centre, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Patrick Ejlerskov
- Biotech Research and Innovation Centre, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge, United Kingdom
| | - Sandeep Gopal
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia
| | - Ava Handley
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia
| | - Leelee Ng
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia
| | - Pedro Moreira
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia
| | - Huikyong Lee
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge, United Kingdom
| | - Shohreh Issazadeh-Navikas
- Biotech Research and Innovation Centre, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - David C Rubinsztein
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge, United Kingdom.,UK Dementia Research Institute, University of Cambridge, Cambridge, United Kingdom
| | - Roger Pocock
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia.,Biotech Research and Innovation Centre, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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17
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Ferreira JV, Rosa Soares A, Ramalho JS, Ribeiro-Rodrigues T, Máximo C, Zuzarte M, Girão H, Pereira P. Exosomes and STUB1/CHIP cooperate to maintain intracellular proteostasis. PLoS One 2019; 14:e0223790. [PMID: 31613922 PMCID: PMC6794069 DOI: 10.1371/journal.pone.0223790] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 09/27/2019] [Indexed: 01/08/2023] Open
Abstract
Deregulation of proteostasis is a main feature of many age-related diseases, often leading to the accumulation of toxic oligomers and insoluble protein aggregates that accumulate intracellularly or in the extracellular space. To understand the mechanisms whereby toxic or otherwise unwanted proteins are secreted to the extracellular space, we inactivated the quality-control and proteostasis regulator ubiquitin ligase STUB1/CHIP. Data indicated that STUB1 deficiency leads both to the intracellular accumulation of protein aggregates and to an increase in the secretion of small extracellular vesicles (sEVs), including exosomes. Secreted sEVs are enriched in ubiquitinated and/or undegraded proteins and protein oligomers. Data also indicates that oxidative stress induces an increase in the release of sEVs in cells depleted from STUB1. Overall, the results presented here suggest that cells use exosomes to dispose of damaged and/or undegraded proteins as a means to reduce intracellular accumulation of proteotoxic material.
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Affiliation(s)
- Joao Vasco Ferreira
- CEDOC, Chronic Diseases Research Centre, NOVA Medical School|Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Campo dos Mártires da Pátria, Lisboa, Portugal
| | - Ana Rosa Soares
- CEDOC, Chronic Diseases Research Centre, NOVA Medical School|Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Campo dos Mártires da Pátria, Lisboa, Portugal
| | - José S. Ramalho
- CEDOC, Chronic Diseases Research Centre, NOVA Medical School|Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Campo dos Mártires da Pátria, Lisboa, Portugal
| | - Teresa Ribeiro-Rodrigues
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, Azinhaga de Santa Comba, Coimbra, Portugal
| | - Catarina Máximo
- CEDOC, Chronic Diseases Research Centre, NOVA Medical School|Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Campo dos Mártires da Pátria, Lisboa, Portugal
| | - Mónica Zuzarte
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, Azinhaga de Santa Comba, Coimbra, Portugal
| | - Henrique Girão
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, Azinhaga de Santa Comba, Coimbra, Portugal
| | - Paulo Pereira
- CEDOC, Chronic Diseases Research Centre, NOVA Medical School|Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Campo dos Mártires da Pátria, Lisboa, Portugal
- * E-mail:
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18
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Roy U. Structure and Function of an Inflammatory Cytokine, Interleukin-2, Analyzed Using the Bioinformatic Approach. Protein J 2019; 38:525-536. [PMID: 31006082 DOI: 10.1007/s10930-019-09833-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The inflammatory cytokine, interleukin-2 (IL-2), is an important regulator of cellular functions. This relatively less studied member of the interleukin protein family is responsible for multiple immuno-modulatory and immuno-stimulatory tasks, like T cell activation, triggering of natural killer cells, inflammation, as well as proliferation and progression of autoimmune diseases and cancers. In this communication we report the temporally variant structural aspects of the IL-2 ligand and its receptor interfaces, based on the available crystal structures. The intended goal of this effort is to generate simulated results that could potentially aid the designs of novel structure based therapeutics.
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Affiliation(s)
- Urmi Roy
- Department of Chemistry & Biomolecular Science, Clarkson University, 8 Clarkson Avenue, Potsdam, NY, 13699-5820, USA.
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19
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Tryptophan 32 mediates SOD1 toxicity in a in vivo motor neuron model of ALS and is a promising target for small molecule therapeutics. Neurobiol Dis 2018; 124:297-310. [PMID: 30528257 DOI: 10.1016/j.nbd.2018.11.025] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2018] [Revised: 11/11/2018] [Accepted: 11/28/2018] [Indexed: 12/21/2022] Open
Abstract
SOD1 misfolding, toxic gain of function, and spread are proposed as a pathological basis of amyotrophic lateral sclerosis (ALS), but the nature of SOD1 toxicity has been difficult to elucidate. Uniquely in SOD1 proteins from humans and other primates, and rarely in other species, a tryptophan residue at position 32 (W32) is predicted to be solvent exposed and to participate in SOD1 misfolding. We hypothesized that W32 is influential in SOD1 acquiring toxicity, as it is known to be important in template-directed misfolding. We tested if W32 contributes to SOD1 cytotoxicity and if it is an appropriate drug target to ameliorate ALS-like neuromuscular deficits in a zebrafish model of motor neuron axon morphology and function (swimming). Embryos injected with human SOD1 variant with W32 substituted for a serine (SOD1W32S) had reduced motor neuron axonopathy and motor deficits compared to those injected with wildtype or disease-associated SOD1. A library of FDA-approved small molecules was ranked with virtual screening based on predicted binding to W32, and subsequently filtered for analogues using a pharmacophore model based on molecular features of the uracil moiety of a small molecule previously predicted to interact with W32 (5'-fluorouridine or 5'-FUrd). Along with testing 5'-FUrd and uridine, a lead candidate from this list was selected based on its lower toxicity and improved blood brain barrier penetrance; telbivudine significantly rescued SOD1 toxicity in a dose-dependent manner. The mechanisms whereby the small molecules ameliorated motor neuron phenotypes were specifically mediated through human SOD1 and its residue W32, because these therapeutics had no measurable impact on the effects of UBQLN4D90A, EtOH, or tryptophan-deficient human SOD1W32S. By substituting W32 for a more evolutionarily conserved residue (serine), we confirmed the significant influence of W32 on human SOD1 toxicity to motor neuron morphology and function; further, we performed pharmaceutical targeting of the W32 residue for rescuing SOD1 toxicity. This unique residue offers future novel insights into SOD1 stability and toxic gain of function, and therefore poses an potential target for drug therapy.
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20
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Pace MC, Xu G, Fromholt S, Howard J, Crosby K, Giasson BI, Lewis J, Borchelt DR. Changes in proteome solubility indicate widespread proteostatic disruption in mouse models of neurodegenerative disease. Acta Neuropathol 2018; 136:919-938. [PMID: 30140941 DOI: 10.1007/s00401-018-1895-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 08/02/2018] [Indexed: 12/17/2022]
Abstract
The deposition of pathologic misfolded proteins in neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease, frontotemporal dementia and amyotrophic lateral sclerosis is hypothesized to burden protein homeostatic (proteostatic) machinery, potentially leading to insufficient capacity to maintain the proteome. This hypothesis has been supported by previous work in our laboratory, as evidenced by the perturbation of cytosolic protein solubility in response to amyloid plaques in a mouse model of Alzheimer's amyloidosis. In the current study, we demonstrate changes in proteome solubility are a common pathology to mouse models of neurodegenerative disease. Pathological accumulations of misfolded tau, α-synuclein and mutant superoxide dismutase 1 in CNS tissues of transgenic mice were associated with changes in the solubility of hundreds of CNS proteins in each model. We observed that changes in proteome solubility were progressive and, using the rTg4510 model of inducible tau pathology, demonstrated that these changes were dependent upon sustained expression of the primary pathologic protein. In all of the models examined, changes in proteome solubility were robust, easily detected, and provided a sensitive indicator of proteostatic disruption. Interestingly, a subset of the proteins that display a shift towards insolubility were common between these different models, suggesting that a specific subset of the proteome is vulnerable to proteostatic disruption. Overall, our data suggest that neurodegenerative proteinopathies modeled in mice impose a burden on the proteostatic network that diminishes the ability of neural cells to prevent aberrant conformational changes that alter the solubility of hundreds of abundant cellular proteins.
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Affiliation(s)
- Michael C Pace
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, McKnight Brain Institute, University of Florida, Gainesville, FL, 32610-0244, USA
| | - Guilian Xu
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, McKnight Brain Institute, University of Florida, Gainesville, FL, 32610-0244, USA
| | - Susan Fromholt
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, McKnight Brain Institute, University of Florida, Gainesville, FL, 32610-0244, USA
| | - John Howard
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, McKnight Brain Institute, University of Florida, Gainesville, FL, 32610-0244, USA
| | - Keith Crosby
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, McKnight Brain Institute, University of Florida, Gainesville, FL, 32610-0244, USA
| | - Benoit I Giasson
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, McKnight Brain Institute, University of Florida, Gainesville, FL, 32610-0244, USA
| | - Jada Lewis
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, McKnight Brain Institute, University of Florida, Gainesville, FL, 32610-0244, USA.
| | - David R Borchelt
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, McKnight Brain Institute, University of Florida, Gainesville, FL, 32610-0244, USA.
- SantaFe Healthcare Alzheimer's Disease Research Center, Gainesville, FL, USA.
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21
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Allison WT, DuVal MG, Nguyen-Phuoc K, Leighton PLA. Reduced Abundance and Subverted Functions of Proteins in Prion-Like Diseases: Gained Functions Fascinate but Lost Functions Affect Aetiology. Int J Mol Sci 2017; 18:E2223. [PMID: 29064456 PMCID: PMC5666902 DOI: 10.3390/ijms18102223] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 10/18/2017] [Accepted: 10/20/2017] [Indexed: 12/12/2022] Open
Abstract
Prions have served as pathfinders that reveal many aspects of proteostasis in neurons. The recent realization that several prominent neurodegenerative diseases spread via a prion-like mechanism illuminates new possibilities for diagnostics and therapeutics. Thus, key proteins in Alzheimer Disease and Amyotrophic lateral sclerosis (ALS), including amyloid-β precursor protein, Tau and superoxide dismutase 1 (SOD1), spread to adjacent cells in their misfolded aggregated forms and exhibit template-directed misfolding to induce further misfolding, disruptions to proteostasis and toxicity. Here we invert this comparison to ask what these prion-like diseases can teach us about the broad prion disease class, especially regarding the loss of these key proteins' function(s) as they misfold and aggregate. We also consider whether functional amyloids might reveal a role for subverted protein function in neurodegenerative disease. Our synthesis identifies SOD1 as an exemplar of protein functions being lost during prion-like protein misfolding, because SOD1 is inherently unstable and loses function in its misfolded disease-associated form. This has under-appreciated parallels amongst the canonical prion diseases, wherein the normally folded prion protein, PrPC, is reduced in abundance in fatal familial insomnia patients and during the preclinical phase in animal models, apparently via proteostatic mechanisms. Thus while template-directed misfolding and infectious properties represent gain-of-function that fascinates proteostasis researchers and defines (is required for) the prion(-like) diseases, loss and subversion of the functions attributed to hallmark proteins in neurodegenerative disease needs to be integrated into design towards effective therapeutics. We propose experiments to uniquely test these ideas.
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Affiliation(s)
- W Ted Allison
- Centre for Prions & Protein Folding Disease, University of Alberta, Edmonton, AB T6G 2M8, Canada.
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada.
- Department of Medical Genetics, University of Alberta, Edmonton, AB T6G 2M8, Canada.
| | - Michèle G DuVal
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada.
| | - Kim Nguyen-Phuoc
- Centre for Prions & Protein Folding Disease, University of Alberta, Edmonton, AB T6G 2M8, Canada.
- Department of Medical Genetics, University of Alberta, Edmonton, AB T6G 2M8, Canada.
| | - Patricia L A Leighton
- Centre for Prions & Protein Folding Disease, University of Alberta, Edmonton, AB T6G 2M8, Canada.
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada.
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22
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Lim L, Kang J, Song J. ALS-causing profilin-1-mutant forms a non-native helical structure in membrane environments. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1859:2161-2170. [PMID: 28847504 DOI: 10.1016/j.bbamem.2017.08.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 07/29/2017] [Accepted: 08/13/2017] [Indexed: 10/19/2022]
Abstract
Despite having physiological functions completely different from superoxide dismutase 1 (SOD1), profilin 1 (PFN1) also carries mutations causing amyotrophic lateral sclerosis (ALS) with a striking similarity to that triggered by SOD1 mutants. Very recently, the C71G-PFN1 has been demonstrated to cause ALS by a gain of toxicity and the acceleration of motor neuron degeneration preceded the accumulation of its aggregates. Here by atomic-resolution NMR determination of conformations and dynamics of WT-PFN1 and C71G-PFN1 in aqueous buffers and in membrane mimetics DMPC/DHPC bicelle and DPC micelle, we deciphered that: 1) the thermodynamic destabilization by C71G transforms PFN1 into coexistence with the unfolded state, which is lacking of any stable tertiary/secondary structures as well as restricted ps-ns backbone motions, thus fundamentally indistinguishable from ALS-causing SOD1 mutants. 2) Most strikingly, while WT-PFN1 only weakly interacts with DMPC/DHPC bicelle without altering the native structure, C71G-PFN1 acquires abnormal capacity in strongly interacting with DMPC/DHPC bicelle and DPC micelle, energetically driven by transforming the highly disordered unfolded state into a non-native helical structure, similar to what has been previously observed on ALS-causing SOD1 mutants. Our results imply that one potential mechanism for C71G-PFN1 to initiate ALS might be the abnormal interaction with membranes as recently established for SOD1 mutants.
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Affiliation(s)
- Liangzhong Lim
- Department of Biological Sciences, Faculty of Science, National University of Singapore, 10 Kent Ridge Crescent, 119260, Singapore
| | - Jian Kang
- Department of Biological Sciences, Faculty of Science, National University of Singapore, 10 Kent Ridge Crescent, 119260, Singapore
| | - Jianxing Song
- Department of Biological Sciences, Faculty of Science, National University of Singapore, 10 Kent Ridge Crescent, 119260, Singapore.
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23
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ALS-linked FUS exerts a gain of toxic function involving aberrant p38 MAPK activation. Sci Rep 2017; 7:115. [PMID: 28273913 PMCID: PMC5428330 DOI: 10.1038/s41598-017-00091-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 01/30/2017] [Indexed: 12/14/2022] Open
Abstract
Mutations in Fused in Sarcoma/Translocated in Liposarcoma (FUS) cause familial forms of amyotrophic lateral sclerosis (ALS), a neurodegenerative disease characterized by progressive axonal degeneration mainly affecting motor neurons. Evidence from transgenic mouse models suggests mutant forms of FUS exert an unknown gain-of-toxic function in motor neurons, but mechanisms underlying this effect remain unknown. Towards this end, we studied the effect of wild type FUS (FUS WT) and three ALS-linked variants (G230C, R521G and R495X) on fast axonal transport (FAT), a cellular process critical for appropriate maintenance of axonal connectivity. All ALS-FUS variants impaired anterograde and retrograde FAT in squid axoplasm, whereas FUS WT had no effect. Misfolding of mutant FUS is implicated in this process, as the molecular chaperone Hsp110 mitigated these toxic effects. Interestingly, mutant FUS-induced impairment of FAT in squid axoplasm and of axonal outgrowth in mammalian primary motor neurons involved aberrant activation of the p38 MAPK pathway, as also reported for ALS-linked forms of Cu, Zn superoxide dismutase (SOD1). Accordingly, increased levels of active p38 MAPK were detected in post-mortem human ALS-FUS brain tissues. These data provide evidence for a novel gain-of-toxic function for ALS-linked FUS involving p38 MAPK activation.
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24
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Protein aggregation and ER stress. Brain Res 2016; 1648:658-666. [PMID: 27037184 DOI: 10.1016/j.brainres.2016.03.044] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 03/26/2016] [Accepted: 03/28/2016] [Indexed: 12/12/2022]
Abstract
Protein aggregation is a common feature of the protein misfolding or conformational diseases, among them most of the neurodegenerative diseases. These disorders are a major scourge, with scarce if any effective therapies at present. Recent research has identified ER stress as a major mechanism implicated in cytotoxicity in these diseases. Whether amyloid-β or tau in Alzheimer's, α-synuclein in Parkinson's, huntingtin in Huntington's disease or other aggregation-prone proteins in many other neurodegenerative diseases, there is a shared pathway of oligomerization and aggregation into amyloid fibrils. There is increasing evidence in recent years that the toxic species, and those that evoke ER stress, are the intermediate oligomeric forms and not the final amyloid aggregates. This review focuses on recent findings on the mechanisms and importance of the development of ER stress upon protein aggregation, especially in neurodegenerative diseases, and possible therapeutic approaches that are being examined. This article is part of a Special Issue entitled SI:ER stress.
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Ruegsegger C, Saxena S. Proteostasis impairment in ALS. Brain Res 2016; 1648:571-579. [PMID: 27033833 DOI: 10.1016/j.brainres.2016.03.032] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2016] [Revised: 03/20/2016] [Accepted: 03/21/2016] [Indexed: 12/13/2022]
Abstract
In physiological conditions the maintenance of the cellular proteome is a prerequisite for optimal cell functioning and cell survival. Additionally, cells need to constantly sense and adapt to their changing environment and associated stressors. Cells achieve this via a set of molecular chaperones, protein clearance pathways as well as stress-associated signaling networks which work together to prevent protein misfolding, its aggregation and accumulation in subcellular compartments. These processes together form the proteostasis network which helps in maintaining cellular proteostasis. Imbalance or impairment in this processes is directly linked to ageing associated disorders such as diabetes, cancer, stroke, metabolic disorders, pulmonary fibrosis, inflammation and neurodegenerative diseases. In this review, we provide insights into the proteostasis process and how its failure governs neurodegenerative disorders with a special focus on Amyotrophic lateral sclerosis (ALS). This article is part of a Special Issue entitled SI:ER stress.
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Affiliation(s)
- Céline Ruegsegger
- Institute of Cell Biology, University of Bern, Baltzerstrasse 4, CH-3012 Bern, Switzerland; Graduate School for Cellular and Biomedical Sciences, University of Bern, CH-3012 Bern, Switzerland
| | - Smita Saxena
- Institute of Cell Biology, University of Bern, Baltzerstrasse 4, CH-3012 Bern, Switzerland.
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Guo H, Cao M, Zou S, Ye B, Dong Y. Cranberry Extract Standardized for Proanthocyanidins Alleviates β-Amyloid Peptide Toxicity by Improving Proteostasis Through HSF-1 in Caenorhabditis elegans Model of Alzheimer's Disease. J Gerontol A Biol Sci Med Sci 2015; 71:1564-1573. [PMID: 26405062 DOI: 10.1093/gerona/glv165] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 08/31/2015] [Indexed: 12/31/2022] Open
Abstract
A growing body of evidence suggests that nutraceuticals with prolongevity properties may delay the onset of Alzheimer's disease (AD). We recently demonstrated that a proanthocyanidins-standardized cranberry extract has properties that prolong life span and promote innate immunity in Caenorhabditis elegans In this article, we report that supplementation of this cranberry extract delayed Aβ toxicity-triggered body paralysis in the C elegans AD model. Genetic analyses indicated that the cranberry-mediated Aβ toxicity alleviation required heat shock transcription factor (HSF)-1 rather than DAF-16 and SKN-1. Moreover, cranberry supplementation increased the transactivity of HSF-1 in an IIS-dependent manner. Further studies found that the cranberry extract relies on HSF-1 to significantly enhance the solubility of proteins in aged worms, implying an improved proteostasis in AD worms. Considering that HSF-1 plays a pivotal role in maintaining proteostasis, our results suggest that cranberry maintains the function of proteostasis through HSF-1, thereby protecting C elegans against Aβ toxicity. Together, our findings elucidated the mechanism whereby cranberry attenuated Aβ toxicity in C elegans and stressed the significance of proteostasis in the prevention of age-related diseases from a practical point of view.
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Affiliation(s)
- Hong Guo
- Department of Biological Sciences, Clemson University, South Carolina.,School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
| | - Min Cao
- Department of Biological Sciences, Clemson University, South Carolina.,Institute for Engaged Aging, Clemson University, Clemson, South Carolina
| | - Sige Zou
- Functional Genomics Unit, Translational Gerontology Branch, National Institute on Aging, Baltimore, Maryland
| | - Boping Ye
- School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
| | - Yuqing Dong
- Department of Biological Sciences, Clemson University, South Carolina. .,Institute for Engaged Aging, Clemson University, Clemson, South Carolina
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Alves CJ, Dariolli R, Jorge FM, Monteiro MR, Maximino JR, Martins RS, Strauss BE, Krieger JE, Callegaro D, Chadi G. Gene expression profiling for human iPS-derived motor neurons from sporadic ALS patients reveals a strong association between mitochondrial functions and neurodegeneration. Front Cell Neurosci 2015; 9:289. [PMID: 26300727 PMCID: PMC4523944 DOI: 10.3389/fncel.2015.00289] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Accepted: 07/14/2015] [Indexed: 01/29/2023] Open
Abstract
Amyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disease that leads to widespread motor neuron death, general palsy and respiratory failure. The most prevalent sporadic ALS form is not genetically inherited. Attempts to translate therapeutic strategies have failed because the described mechanisms of disease are based on animal models carrying specific gene mutations and thus do not address sporadic ALS. In order to achieve a better approach to study the human disease, human induced pluripotent stem cell (hiPSC)-differentiated motor neurons were obtained from motor nerve fibroblasts of sporadic ALS and non-ALS subjects using the STEMCCA Cre-Excisable Constitutive Polycistronic Lentivirus system and submitted to microarray analyses using a whole human genome platform. DAVID analyses of differentially expressed genes identified molecular function and biological process-related genes through Gene Ontology. REVIGO highlighted the related functions mRNA and DNA binding, GTP binding, transcription (co)-repressor activity, lipoprotein receptor binding, synapse organization, intracellular transport, mitotic cell cycle and cell death. KEGG showed pathways associated with Parkinson's disease and oxidative phosphorylation, highlighting iron homeostasis, neurotrophic functions, endosomal trafficking and ERK signaling. The analysis of most dysregulated genes and those representative of the majority of categorized genes indicates a strong association between mitochondrial function and cellular processes possibly related to motor neuron degeneration. In conclusion, iPSC-derived motor neurons from motor nerve fibroblasts of sporadic ALS patients may recapitulate key mechanisms of neurodegeneration and may offer an opportunity for translational investigation of sporadic ALS. Large gene profiling of differentiated motor neurons from sporadic ALS patients highlights mitochondrial participation in the establishment of autonomous mechanisms associated with sporadic ALS.
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Affiliation(s)
- Chrystian J Alves
- Department of Neurology, Neuroregeneration Center, University of São Paulo School of Medicine, University of São Paulo São Paulo, Brazil
| | - Rafael Dariolli
- Laboratory of Genetics and Molecular Cardiology/LIM13, Heart Institute, University of São Paulo School of Medicine São Paulo, Brazil
| | - Frederico M Jorge
- Department of Neurology, Neuroregeneration Center, University of São Paulo School of Medicine, University of São Paulo São Paulo, Brazil
| | - Matheus R Monteiro
- Department of Neurology, Neuroregeneration Center, University of São Paulo School of Medicine, University of São Paulo São Paulo, Brazil
| | - Jessica R Maximino
- Department of Neurology, Neuroregeneration Center, University of São Paulo School of Medicine, University of São Paulo São Paulo, Brazil
| | - Roberto S Martins
- Department of Neurosurgery, Surgical Center of Functional Neurosurgery, Clinics Hospital of University of São Paulo São Paulo, Brazil
| | - Bryan E Strauss
- Viral Vector Laboratory, Center for Translational Investigation in Oncology/LIM24, Cancer Institute of São Paulo, University of São Paulo School of Medicine São Paulo, Brazil
| | - José E Krieger
- Laboratory of Genetics and Molecular Cardiology/LIM13, Heart Institute, University of São Paulo School of Medicine São Paulo, Brazil
| | - Dagoberto Callegaro
- Department of Neurology, Neuroregeneration Center, University of São Paulo School of Medicine, University of São Paulo São Paulo, Brazil
| | - Gerson Chadi
- Department of Neurology, Neuroregeneration Center, University of São Paulo School of Medicine, University of São Paulo São Paulo, Brazil
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Boopathy S, Silvas TV, Tischbein M, Jansen S, Shandilya SM, Zitzewitz JA, Landers JE, Goode BL, Schiffer CA, Bosco DA. Structural basis for mutation-induced destabilization of profilin 1 in ALS. Proc Natl Acad Sci U S A 2015; 112:7984-9. [PMID: 26056300 PMCID: PMC4491777 DOI: 10.1073/pnas.1424108112] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Mutations in profilin 1 (PFN1) are associated with amyotrophic lateral sclerosis (ALS); however, the pathological mechanism of PFN1 in this fatal disease is unknown. We demonstrate that ALS-linked mutations severely destabilize the native conformation of PFN1 in vitro and cause accelerated turnover of the PFN1 protein in cells. This mutation-induced destabilization can account for the high propensity of ALS-linked variants to aggregate and also provides rationale for their reported loss-of-function phenotypes in cell-based assays. The source of this destabilization is illuminated by the X-ray crystal structures of several PFN1 proteins, revealing an expanded cavity near the protein core of the destabilized M114T variant. In contrast, the E117G mutation only modestly perturbs the structure and stability of PFN1, an observation that reconciles the occurrence of this mutation in the control population. These findings suggest that a destabilized form of PFN1 underlies PFN1-mediated ALS pathogenesis.
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Affiliation(s)
- Sivakumar Boopathy
- Department of Neurology, University of Massachusetts Medical School, Worcester, MA 01605
| | - Tania V Silvas
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605
| | - Maeve Tischbein
- Department of Neurology, University of Massachusetts Medical School, Worcester, MA 01605
| | - Silvia Jansen
- Department of Biology, Brandeis University, Waltham, MA 02453
| | - Shivender M Shandilya
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605
| | - Jill A Zitzewitz
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605
| | - John E Landers
- Department of Neurology, University of Massachusetts Medical School, Worcester, MA 01605
| | - Bruce L Goode
- Department of Biology, Brandeis University, Waltham, MA 02453
| | - Celia A Schiffer
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605
| | - Daryl A Bosco
- Department of Neurology, University of Massachusetts Medical School, Worcester, MA 01605; Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605;
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Roberts RF, Wade-Martins R, Alegre-Abarrategui J. Direct visualization of alpha-synuclein oligomers reveals previously undetected pathology in Parkinson's disease brain. Brain 2015; 138:1642-57. [PMID: 25732184 PMCID: PMC4614141 DOI: 10.1093/brain/awv040] [Citation(s) in RCA: 183] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 12/15/2014] [Indexed: 11/13/2022] Open
Abstract
Oligomeric forms of alpha-synuclein are emerging as key mediators of pathogenesis in Parkinson's disease. Our understanding of the exact contribution of alpha-synuclein oligomers to disease is limited by the lack of a technique for their specific detection. We describe a novel method, the alpha-synuclein proximity ligation assay, which specifically recognizes alpha-synuclein oligomers. In a blinded study with post-mortem brain tissue from patients with Parkinson's disease (n = 8, age range 73-92 years, four males and four females) and age- and sex-matched controls (n = 8), we show that the alpha-synuclein proximity ligation assay reveals previously unrecognized pathology in the form of extensive diffuse deposition of alpha-synuclein oligomers. These oligomers are often localized, in the absence of Lewy bodies, to neuroanatomical regions mildly affected in Parkinson's disease. Diffuse alpha-synuclein proximity ligation assay signal is significantly more abundant in patients compared to controls in regions including the cingulate cortex (1.6-fold increase) and the reticular formation of the medulla (6.5-fold increase). In addition, the alpha-synuclein proximity ligation assay labels very early perikaryal aggregates in morphologically intact neurons that may precede the development of classical Parkinson's disease lesions, such as pale bodies or Lewy bodies. Furthermore, the alpha-synuclein proximity ligation assay preferentially detects early-stage, loosely compacted lesions such as pale bodies in patient tissue, whereas Lewy bodies, considered heavily compacted late lesions are only very exceptionally stained. The alpha-synuclein proximity ligation assay preferentially labels alpha-synuclein oligomers produced in vitro compared to monomers and fibrils, while stained oligomers in human brain display a distinct intermediate proteinase K resistance, suggesting the detection of a conformer that is different from both physiological, presynaptic alpha-synuclein (proteinase K-sensitive) and highly aggregated alpha-synuclein within Lewy bodies (proteinase K-resistant). These disease-associated conformers represent previously undetected Parkinson's disease pathology uncovered by the alpha-synuclein proximity ligation assay.
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Affiliation(s)
- Rosalind F Roberts
- 1 Department of Physiology, Anatomy and Genetics, University of Oxford, Le Gros Clark Building, South Parks Road, Oxford OX1 3QX, UK 2 Oxford Parkinson's Disease Centre, University of Oxford, Le Gros Clark Building, South Parks Road, Oxford, OX1 3QX, UK
| | - Richard Wade-Martins
- 1 Department of Physiology, Anatomy and Genetics, University of Oxford, Le Gros Clark Building, South Parks Road, Oxford OX1 3QX, UK 2 Oxford Parkinson's Disease Centre, University of Oxford, Le Gros Clark Building, South Parks Road, Oxford, OX1 3QX, UK
| | - Javier Alegre-Abarrategui
- 1 Department of Physiology, Anatomy and Genetics, University of Oxford, Le Gros Clark Building, South Parks Road, Oxford OX1 3QX, UK 2 Oxford Parkinson's Disease Centre, University of Oxford, Le Gros Clark Building, South Parks Road, Oxford, OX1 3QX, UK
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Charan RA, LaVoie MJ. Pathologic and therapeutic implications for the cell biology of parkin. Mol Cell Neurosci 2015; 66:62-71. [PMID: 25697646 DOI: 10.1016/j.mcn.2015.02.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 02/07/2015] [Accepted: 02/15/2015] [Indexed: 01/07/2023] Open
Abstract
Mutations in the E3 ligase parkin are the most common cause of autosomal recessive Parkinson's disease (PD), but it is believed that parkin dysfunction may also contribute to idiopathic PD. Since its discovery, parkin has been implicated in supporting multiple neuroprotective pathways, many revolving around the maintenance of mitochondrial health quality control and governance of cell survival. Recent advances across the structure, biochemistry, and cell biology of parkin have provided great insights into the etiology of parkin-linked and idiopathic PD and may ultimately generate novel therapeutic strategies to slow or halt disease progression. This review describes the various pathways in which parkin acts and the mechanisms by which parkin may be targeted for therapeutic intervention. This article is part of a Special Issue entitled 'Neuronal Protein'.
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Affiliation(s)
- Rakshita A Charan
- Ann Romney Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital, Boston, USA; Harvard Medical School, Boston, USA
| | - Matthew J LaVoie
- Ann Romney Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital, Boston, USA; Harvard Medical School, Boston, USA
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31
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Khodakarami A, Saez I, Mels J, Vilchez D. Mediation of organismal aging and somatic proteostasis by the germline. Front Mol Biosci 2015; 2:3. [PMID: 25988171 PMCID: PMC4428440 DOI: 10.3389/fmolb.2015.00003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Accepted: 01/07/2015] [Indexed: 12/22/2022] Open
Abstract
Experimental interventions that reduce reproduction cause an extension in lifespan. In invertebrates, such as Caenorhabditis elegans, the aging of the soma is regulated by signals from the germline. Indeed, ablation of germ cells significantly extends lifespan. Notably, germline-deficient animals exhibit heightened resistance to proteotoxic stress. This phenotype correlates with increased potential of intracellular clearance mechanisms such as the proteasome and autophagy in somatic tissues. Here we review the molecular mechanisms by which signals from the germline regulate lifespan in C. elegans with special emphasis on clearance mechanisms.
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Affiliation(s)
- Amirabbas Khodakarami
- Cologne Excellence Cluster for Cellular Stress Responses in Aging-Associated Diseases, University of Cologne Cologne, Germany
| | - Isabel Saez
- Cologne Excellence Cluster for Cellular Stress Responses in Aging-Associated Diseases, University of Cologne Cologne, Germany
| | - Johanna Mels
- Cologne Excellence Cluster for Cellular Stress Responses in Aging-Associated Diseases, University of Cologne Cologne, Germany
| | - David Vilchez
- Cologne Excellence Cluster for Cellular Stress Responses in Aging-Associated Diseases, University of Cologne Cologne, Germany
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Abstract
SIGNIFICANCE Impairment of the ubiquitin-proteasome system (UPS) has been implicated in the pathogenesis of a wide variety of neurodegenerative disorders, including Alzheimer's, Parkinson's, and Huntington's diseases. The most significant risk factor for the development of these disorders is aging, which is associated with a progressive decline in UPS activity and the accumulation of oxidatively modified proteins. To date, no therapies have been developed that can specifically up-regulate this system. RECENT ADVANCES In the neurodegenerative brain, dysfunction of the UPS has been associated with the deposition of ubiquitinated protein aggregates and widespread disruption of the proteostasis network. Recent research has identified further evidence of impairment in substrate ubiquitination and proteasomal degradation, which could contribute to the loss of cellular proteostasis in neurodegenerative disease. Novel strategies for activation of the UPS by genetic manipulation and treatment with synthetic compounds have also recently been identified. CRITICAL ISSUES Here, we discuss the specific roles of the UPS in the healthy central nervous system and establish how dysfunctional components can contribute to neurotoxicity in the context of disease. FUTURE DIRECTIONS Knowledge of the UPS components that are specifically or preferentially involved in neurodegenerative disease will be critical in the development of targeted therapies which aim at limiting the accumulation of misfolded proteins without gross disturbance of this major proteolytic pathway.
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Affiliation(s)
- Chris McKinnon
- Department of Neurodegenerative Disease, University College London Institute of Neurology , London, United Kingdom
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33
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The role of protein clearance mechanisms in organismal ageing and age-related diseases. Nat Commun 2014; 5:5659. [DOI: 10.1038/ncomms6659] [Citation(s) in RCA: 442] [Impact Index Per Article: 44.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 10/24/2014] [Indexed: 12/27/2022] Open
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Schapansky J, Nardozzi JD, LaVoie MJ. The complex relationships between microglia, alpha-synuclein, and LRRK2 in Parkinson's disease. Neuroscience 2014; 302:74-88. [PMID: 25284317 DOI: 10.1016/j.neuroscience.2014.09.049] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Revised: 09/22/2014] [Accepted: 09/23/2014] [Indexed: 12/19/2022]
Abstract
The proteins alpha-synuclein (αSyn) and leucine rich repeat kinase 2 (LRRK2) are both key players in the pathogenesis of the neurodegenerative disorder Parkinson's disease (PD), but establishing a functional link between the two proteins has proven elusive. Research studies for these two proteins have traditionally and justifiably focused in neuronal cells, but recent studies indicate that each protein could play a greater pathological role elsewhere. αSyn is expressed at high levels within neurons, but they also secrete the protein into the extracellular milieu, where it can have broad ranging effects in the nervous system and relevance to disease etiology. Similarly, low neuronal LRRK2 expression and activity suggests that LRRK2-related functions could be more relevant in cells with higher expression, such as brain-resident microglia. Microglia are monocytic immune cells that protect neurons from noxious stimuli, including pathological αSyn species, and microglial activation is believed to contribute to neuroinflammation and neuronal death in PD. Interestingly, both αSyn and LRRK2 can be linked to microglial function. Secreted αSyn can directly activate microglia, and can be taken up by microglia for clearance, while LRRK2 has been implicated in the intrinsic regulation of microglial activation and of lysosomal degradation processes. Based on these observations, the present review will focus on how PD-associated mutations in LRRK2 could potentially alter microglial biology with respect to neuronally secreted αSyn, resulting in cell dysfunction and neurodegeneration.
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Affiliation(s)
- J Schapansky
- Center for Neurologic Diseases, Harvard Medical School, and Brigham and Women's Hospital, Boston, MA 02115, United States
| | - J D Nardozzi
- Center for Neurologic Diseases, Harvard Medical School, and Brigham and Women's Hospital, Boston, MA 02115, United States
| | - M J LaVoie
- Center for Neurologic Diseases, Harvard Medical School, and Brigham and Women's Hospital, Boston, MA 02115, United States.
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Charan RA, Johnson BN, Zaganelli S, Nardozzi JD, LaVoie MJ. Inhibition of apoptotic Bax translocation to the mitochondria is a central function of parkin. Cell Death Dis 2014; 5:e1313. [PMID: 24991765 PMCID: PMC4123072 DOI: 10.1038/cddis.2014.278] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 04/21/2014] [Accepted: 05/21/2014] [Indexed: 11/09/2022]
Abstract
Parkinson's disease (PD) is the second most prevalent neurodegenerative disorder, affecting 1–3% of the population over 65. Mutations in the ubiquitin E3 ligase parkin are the most common cause of autosomal recessive PD. The parkin protein possesses potent cell-protective properties and has been mechanistically linked to both the regulation of apoptosis and the turnover of damaged mitochondria. Here, we explored these two functions of parkin and the relative scale of these processes in various cell types. While biochemical analyses and subcellular fractionation were sufficient to observe robust parkin-dependent mitophagy in immortalized cells, higher resolution techniques appear to be required for primary culture systems. These approaches, however, did affirm a critical role for parkin in the regulation of apoptosis in primary cultured neurons and all other cells studied. Our prior work demonstrated that parkin-dependent ubiquitination of endogenous Bax inhibits its mitochondrial translocation and can account for the anti-apoptotic effects of parkin. Having found a central role for parkin in the regulation of apoptosis, we further investigated the parkin-Bax interaction. We observed that the BH3 domain of Bax is critical for its recognition by parkin, and identified two lysines that are crucial for parkin-dependent regulation of Bax translocation. Last, a disease-linked mutation in parkin failed to influence Bax translocation to mitochondria after apoptotic stress. Taken together, our data suggest that regulation of apoptosis by the inhibition of Bax translocation is a prevalent physiological function of parkin regardless of the kind of cell stress, preventing overt cell death and supporting cell viability during mitochondrial injury and repair.
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Affiliation(s)
- R A Charan
- 1] Harvard Medical School, Boston, MA, USA [2] Department of Neurology, Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - B N Johnson
- 1] Harvard Medical School, Boston, MA, USA [2] Department of Neurology, Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - S Zaganelli
- Department of Neurology, Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - J D Nardozzi
- 1] Harvard Medical School, Boston, MA, USA [2] Department of Neurology, Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - M J LaVoie
- 1] Harvard Medical School, Boston, MA, USA [2] Department of Neurology, Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
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Saez I, Vilchez D. The Mechanistic Links Between Proteasome Activity, Aging and Age-related Diseases. Curr Genomics 2014; 15:38-51. [PMID: 24653662 PMCID: PMC3958958 DOI: 10.2174/138920291501140306113344] [Citation(s) in RCA: 219] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Revised: 01/13/2014] [Accepted: 01/15/2014] [Indexed: 01/17/2023] Open
Abstract
Damaged and misfolded proteins accumulate during the aging process, impairing cell function and tissue homeostasis. These perturbations to protein homeostasis (proteostasis) are hallmarks of age-related neurodegenerative disorders such as Alzheimer’s, Parkinson’s or Huntington’s disease. Damaged proteins are degraded by cellular clearance mechanisms such as the proteasome, a key component of the proteostasis network. Proteasome activity declines during aging, and proteasomal dysfunction is associated with late-onset disorders. Modulation of proteasome activity extends lifespan and protects organisms from symptoms associated with proteostasis disorders. Here we review the links between proteasome activity, aging and neurodegeneration. Additionally, strategies to modulate proteasome activity and delay the onset of diseases associated to proteasomal dysfunction are discussed herein.
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Affiliation(s)
- Isabel Saez
- Cologne Excellence Cluster for Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Co-logne, Joseph Stelzmann Strasse 26, 50931 Cologne, Germany
| | - David Vilchez
- Cologne Excellence Cluster for Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Co-logne, Joseph Stelzmann Strasse 26, 50931 Cologne, Germany
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37
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Proteostasis and aging of stem cells. Trends Cell Biol 2014; 24:161-70. [DOI: 10.1016/j.tcb.2013.09.002] [Citation(s) in RCA: 108] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Revised: 09/04/2013] [Accepted: 09/04/2013] [Indexed: 12/13/2022]
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38
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Rotunno MS, Bosco DA. An emerging role for misfolded wild-type SOD1 in sporadic ALS pathogenesis. Front Cell Neurosci 2013; 7:253. [PMID: 24379756 PMCID: PMC3863749 DOI: 10.3389/fncel.2013.00253] [Citation(s) in RCA: 167] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2013] [Accepted: 11/25/2013] [Indexed: 12/12/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder that targets motor neurons, leading to paralysis and death within a few years of disease onset. While several genes have been linked to the inheritable, or familial, form of ALS, much less is known about the cause(s) of sporadic ALS, which accounts for ~90% of ALS cases. Due to the clinical similarities between familial and sporadic ALS, it is plausible that both forms of the disease converge on a common pathway and, therefore, involve common factors. Recent evidence suggests the Cu,Zn-superoxide dismutase (SOD1) protein to be one such factor that is common to both sporadic and familial ALS. In 1993, mutations were uncovered in SOD1 that represent the first known genetic cause of familial ALS. While the exact mechanism of mutant-SOD1 toxicity is still not known today, most evidence points to a gain of toxic function that stems, at least in part, from the propensity of this protein to misfold. In the wild-type SOD1 protein, non-genetic perturbations such as metal depletion, disruption of the quaternary structure, and oxidation, can also induce SOD1 to misfold. In fact, these aforementioned post-translational modifications cause wild-type SOD1 to adopt a “toxic conformation” that is similar to familial ALS-linked SOD1 variants. These observations, together with the detection of misfolded wild-type SOD1 within human post-mortem sporadic ALS samples, have been used to support the controversial hypothesis that misfolded forms of wild-type SOD1 contribute to sporadic ALS pathogenesis. In this review, we present data from the literature that both support and contradict this hypothesis. We also discuss SOD1 as a potential therapeutic target for both familial and sporadic ALS.
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Affiliation(s)
- Melissa S Rotunno
- Department of Neurology, University of Massachusetts Medical Center Worcester, MA, USA
| | - Daryl A Bosco
- Department of Neurology, University of Massachusetts Medical Center Worcester, MA, USA
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Surmeier DJ, Guzman JN, Sanchez J, Schumacker PT. Physiological phenotype and vulnerability in Parkinson's disease. Cold Spring Harb Perspect Med 2013; 2:a009290. [PMID: 22762023 DOI: 10.1101/cshperspect.a009290] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
This review will focus on the principles underlying the hypothesis that neuronal physiological phenotype-how a neuron generates and regulates action potentials-makes a significant contribution to its vulnerability in Parkinson's disease (PD) and aging. A cornerstone of this hypothesis is that the maintenance of ionic gradients underlying excitability can pose a significant energetic burden for neurons, particularly those that have sustained residence times at depolarized membrane potentials, broad action potentials, prominent Ca(2+) entry, and modest intrinsic Ca(2+) buffering capacity. This energetic burden is shouldered in neurons primarily by mitochondria, the sites of cellular respiration. Mitochondrial respiration increases the production of damaging superoxide and other reactive oxygen species (ROS) that have widely been postulated to contribute to cellular aging and PD. Many of the genetic mutations and toxins associated with PD compromise mitochondrial function, providing a mechanistic linkage between known risk factors and cellular physiology that could explain the pattern of pathology in PD. Because much of the mitochondrial burden created by this at-risk phenotype is created by Ca(2+) entry through L-type voltage-dependent channels for which there are antagonists approved for human use, a neuroprotective strategy to reduce this burden is feasible.
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Affiliation(s)
- D James Surmeier
- Department of Physiology, Northwestern University, Chicago, Illinois, USA.
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Mulligan VK, Chakrabartty A. Protein misfolding in the late-onset neurodegenerative diseases: Common themes and the unique case of amyotrophic lateral sclerosis. Proteins 2013; 81:1285-303. [DOI: 10.1002/prot.24285] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2012] [Revised: 02/27/2013] [Accepted: 02/28/2013] [Indexed: 12/12/2022]
Affiliation(s)
| | - Avijit Chakrabartty
- Department of Biochemistry; Toronto Ontario M5G 1L7 Canada
- Department of Medical Biophysics; University of Toronto; Toronto Ontario M5G 1L7 Canada
- Campbell Family Institute for Cancer Research, Ontario Cancer Institute/University Health Network; Toronto Ontario M5G 1L7 Canada
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41
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Liu M, Bender SA, Cuny GD, Sherman W, Glicksman M, Ray SS. Type II kinase inhibitors show an unexpected inhibition mode against Parkinson's disease-linked LRRK2 mutant G2019S. Biochemistry 2013; 52:1725-36. [PMID: 23379419 PMCID: PMC3966205 DOI: 10.1021/bi3012077] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A number of well-known type II inhibitors (ATP-noncompetitive) that bind kinases in their DFG-out conformation were tested against wild-type LRRK2 and the most common Parkinson's disease-linked mutation, G2019S. We found that traditional type II inhibitors exhibit surprising variability in their inhibition mechanism between the wild type (WT) and the G2019S mutant of LRRK2. The type II kinase inhibitors were found to work in an ATP-competitive fashion against the G2019S mutant, whereas they appear to follow the expected noncompetitive mechanism against WT. Because the G2019S mutation lies in the DXG motif (DYG in LRRK2 but DFG in most other kinases) of the activation loop, we explored the structural consequence of the mutation on loop dynamics using an enhanced sampling method called metadynamics. The simulations suggest that the G2019S mutation stabilizes the DYG-in state of LRRK2 through a series of hydrogen bonds, leading to an increase in the conformational barrier between the active and inactive forms of the enzyme and a relative stabilization of the active form. The conformational bias toward the active form of LRRK2 mutants has two primary consequences. (1) The mutant enzyme becomes hyperactive, a known contributor to the Parkinsonian phenotype, as a consequence of being "locked" into the activated state, and (2) the mutation creates an unusual allosteric pocket that can bind type II inhibitors but in an ATP-competitive fashion. Our results suggest that developing type II inhibitors, which are generally considered superior to type I inhibitors because of desirable selectivity profiles, might be especially challenging for the G2019S LRRK2 mutant.
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Affiliation(s)
- Min Liu
- Harvard NeuroDiscovery Center, Harvard University, 65 Landsdowne St., #452, Cambridge, MA 02139
| | | | - Gregory D Cuny
- Harvard NeuroDiscovery Center, Harvard University, 65 Landsdowne St., #452, Cambridge, MA 02139
| | - Woody Sherman
- Schrodinger, 120 W. 45 Street, New York, NY, 10036
- Proteus Discovery Inc. 411 Massachusetts avenue, Cambridge, MA 02139-410
| | - Marcie Glicksman
- Harvard NeuroDiscovery Center, Harvard University, 65 Landsdowne St., #452, Cambridge, MA 02139
| | - Soumya S. Ray
- Harvard NeuroDiscovery Center, Harvard University, 65 Landsdowne St., #452, Cambridge, MA 02139
- Department of Neurology, Brigham and Women’s Hospital
- Center for Neurologic Diseases, Brigham and Women’s Hospital
- Proteus Discovery Inc. 411 Massachusetts avenue, Cambridge, MA 02139-410
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42
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Penke B, Tóth AM, Földi I, Szűcs M, Janáky T. Intraneuronal β-amyloid and its interactions with proteins and subcellular organelles. Electrophoresis 2012; 33:3608-16. [PMID: 23161402 DOI: 10.1002/elps.201200297] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2012] [Revised: 08/09/2012] [Accepted: 08/21/2012] [Indexed: 11/09/2022]
Abstract
Amyloidogenic aggregation and misfolding of proteins are linked to neurodegeneration. The mechanism of neurodegeneration in Alzheimer's disease, which gives rise to severe neuronal death and memory loss, is not yet fully understood. The amyloid hypothesis remains the most accepted theory for the pathomechanism of the disease. It was suggested that β-amyloid accumulation may play a key role in initiating the neurodegenerative processes. The recent intracellular β-amyloid (iAβ) hypothesis emphasizes the primary role of iAβ to initiate the disease by interaction with cytoplasmic proteins and cell organelles, thereby triggering apoptosis. Sophisticated methods (proteomics, protein microarray, and super resolution microscopy) have been used for studying iAβ interactions with proteins and membraneous structures. The present review summarizes the studies on the origin of iAβ and the base of its neurotoxicity: interactions with cytosolic proteins and several cell organelles such as endoplasmic reticulum, endosomes, lysosomes, ribosomes, mitochondria, and the microtubular system.
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Affiliation(s)
- Botond Penke
- Department of Medical Chemistry, University of Szeged, Szeged, Hungary.
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Compartmentalization of superoxide dismutase 1 (SOD1G93A) aggregates determines their toxicity. Proc Natl Acad Sci U S A 2012; 109:15811-6. [PMID: 22967507 DOI: 10.1073/pnas.1205829109] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Neurodegenerative diseases constitute a class of illnesses marked by pathological protein aggregation in the brains of affected individuals. Although these disorders are invariably characterized by the degeneration of highly specific subpopulations of neurons, protein aggregation occurs in all cells, which indicates that toxicity arises only in particular cell biological contexts. Aggregation-associated disorders are unified by a common cell biological feature: the deposition of the culprit proteins in inclusion bodies. The precise function of these inclusions remains unclear. The starting point for uncovering the origins of disease pathology must therefore be a thorough understanding of the general cell biological function of inclusions and their potential role in modulating the consequences of aggregation. Here, we show that in human cells certain aggregate inclusions are active compartments. We find that toxic aggregates localize to one of these compartments, the juxtanuclear quality control compartment (JUNQ), and interfere with its quality control function. The accumulation of SOD1G93A aggregates sequesters Hsp70, preventing the delivery of misfolded proteins to the proteasome. Preventing the accumulation of SOD1G93A in the JUNQ by enhancing its sequestration in an insoluble inclusion reduces the harmful effects of aggregation on cell viability.
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Johnson BN, Charan RA, LaVoie MJ. Recognizing the cooperative and independent mitochondrial functions of Parkin and PINK1. Cell Cycle 2012; 11:2775-6. [PMID: 22801534 PMCID: PMC3419053 DOI: 10.4161/cc.21261] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Comment on: Johnson BN, et al. Proc Natl Acad Sci USA 2012; 109:6283-8.
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Krebs CE, Paisán-Ruiz C. The use of next-generation sequencing in movement disorders. Front Genet 2012; 3:75. [PMID: 22593763 PMCID: PMC3351011 DOI: 10.3389/fgene.2012.00075] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Accepted: 04/21/2012] [Indexed: 12/12/2022] Open
Abstract
New advances in genomic technology are being introduced at a greater speed and are revolutionizing the field of genetics for both complex and Mendelian diseases. For instance, during the past few years, genome-wide association studies (GWAS) have identified a large number of significant associations between genomic loci and movement disorders such as Parkinson's disease and progressive supranuclear palsy. GWAS are carried out through the use of high-throughput SNP genotyping arrays, which are also used to perform linkage analyses in families previously considered statistically underpowered for genetic analyses. In inherited movement disorders, using this latter technology, it has repeatedly been shown that mutations in a single gene can lead to different phenotypes, while the same clinical entity can be caused by mutations in different genes. This is being highlighted with the use of next-generation sequencing technologies and leads to the search for genes or genetic modifiers that contribute to the phenotypic expression of movement disorders. Establishing an accurate genome-epigenome-phenotype relationship is becoming a major challenge in the post-genomic research that should be facilitated through the implementation of both functional and cellular analyses.
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Affiliation(s)
- Catharine E Krebs
- Department of Neurology, Mount Sinai School of Medicine New York, NY, USA
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The ubiquitin E3 ligase parkin regulates the proapoptotic function of Bax. Proc Natl Acad Sci U S A 2012; 109:6283-8. [PMID: 22460798 DOI: 10.1073/pnas.1113248109] [Citation(s) in RCA: 144] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Autosomal recessive loss-of-function mutations within the PARK2 gene functionally inactivate the E3 ubiquitin ligase parkin, resulting in neurodegeneration of catecholaminergic neurons and a familial form of Parkinson disease. Current evidence suggests both a mitochondrial function for parkin and a neuroprotective role, which may in fact be interrelated. The antiapoptotic effects of parkin have been widely reported, and may involve fundamental changes in the threshold for apoptotic cytochrome c release, but the substrate(s) involved in parkin dependent protection had not been identified. Here, we demonstrate the parkin-dependent ubiquitination of endogenous Bax comparing primary cultured neurons from WT and parkin KO mice and using multiple parkin-overexpressing cell culture systems. The direct ubiquitination of purified Bax was also observed in vitro following incubation with recombinant parkin. We found that parkin prevented basal and apoptotic stress-induced translocation of Bax to the mitochondria. Moreover, an engineered ubiquitination-resistant form of Bax retained its apoptotic function, but Bax KO cells complemented with lysine-mutant Bax did not manifest the antiapoptotic effects of parkin that were observed in cells expressing WT Bax. These data suggest that Bax is the primary substrate responsible for the antiapoptotic effects of parkin, and provide mechanistic insight into at least a subset of the mitochondrial effects of parkin.
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Nicotinamide, NAD(P)(H), and Methyl-Group Homeostasis Evolved and Became a Determinant of Ageing Diseases: Hypotheses and Lessons from Pellagra. Curr Gerontol Geriatr Res 2012; 2012:302875. [PMID: 22536229 PMCID: PMC3318212 DOI: 10.1155/2012/302875] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2011] [Accepted: 12/19/2011] [Indexed: 01/22/2023] Open
Abstract
Compartmentalized redox faults are common to ageing diseases. Dietary constituents are catabolized to NAD(H) donating electrons producing proton-based bioenergy in coevolved, cross-species and cross-organ networks. Nicotinamide and NAD deficiency from poor diet or high expenditure causes pellagra, an ageing and dementing disorder with lost robustness to infection and stress. Nicotinamide and stress induce Nicotinamide-N-methyltransferase (NNMT) improving choline retention but consume methyl groups. High NNMT activity is linked to Parkinson's, cancers, and diseases of affluence. Optimising nicotinamide and choline/methyl group availability is important for brain development and increased during our evolution raising metabolic and methylome ceilings through dietary/metabolic symbiotic means but strict energy constraints remain and life-history tradeoffs are the rule. An optimal energy, NAD and methyl group supply, avoiding hypo and hyper-vitaminoses nicotinamide and choline, is important to healthy ageing and avoids utilising double-edged symbionts or uncontrolled autophagy or reversions to fermentation reactions in inflammatory and cancerous tissue that all redistribute NAD(P)(H), but incur high allostatic costs.
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Abstract
Parkinson's disease (PD) is the most common age-related motoric neurodegenerative disease initially described in the 1800's by James Parkinson as the 'Shaking Palsy'. Loss of the neurotransmitter dopamine was recognized as underlying the pathophysiology of the motor dysfunction; subsequently discovery of dopamine replacement therapies brought substantial symptomatic benefit to PD patients. However, these therapies do not fully treat the clinical syndrome nor do they alter the natural history of this disorder motivating clinicians and researchers to further investigate the clinical phenotype, pathophysiology/pathobiology and etiology of this devastating disease. Although the exact cause of sporadic PD remains enigmatic studies of familial and rare toxicant forms of this disorder have laid the foundation for genome wide explorations and environmental studies. The combination of methodical clinical evaluation, systematic pathological studies and detailed genetic analyses have revealed that PD is a multifaceted disorder with a wide-range of clinical symptoms and pathology that include regions outside the dopamine system. One common thread in PD is the presence of intracytoplasmic inclusions that contain the protein, α-synuclein. The presence of toxic aggregated forms of α-synuclein (e.g., amyloid structures) are purported to be a harbinger of subsequent pathology. In fact, PD is both a cerebral amyloid disease and the most common synucleinopathy, that is, diseases that display accumulations of α-synuclein. Here we present our current understanding of PD etiology, pathology, clinical symptoms and therapeutic approaches with an emphasis on misfolded α-synuclein.
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Affiliation(s)
- Timothy R. Mhyre
- Department of Neuroscience, Georgetown University Medical Center, NRB EP08, 3970 Reservoir Road NW, 20057, Washington, DC, USA,
| | - James T. Boyd
- University of Vermont College of Medicine, 1 South Prospect Street, DU-Arnold 4416-UHC, 05401, Burlington, VT, USA,
| | - Robert W. Hamill
- Department of Neurology, University of Vermont College of Medicine, 89 Beaumont Avenue, Given Hall Room C225, 05405, Burlington, VT, USA,
| | - Kathleen A. Maguire-Zeiss
- Department of Neuroscience, Center for Neural Injury and RecoveryGeorgetown University Medical Center, 3970 Reservoir Road, NW NRB EP08, 20057, Washington, DC, USA,
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